The tables in our database is where the information about individual objects is aggregated. The tables from our database are open for direct exploration in read–only mode as shown in some of our use case jupyter notebooks (https://github.com/alercebroker/usecases), although we recommend accessing them using our different APIs.
ZTF alert packets contain associated stamps, metadata and information related to previous detections. As
alerts arrive we store the original AVRO files in repository for future analysis and extract a selection of the fields contained in these packets to be added directly to a PostgreSQL database engine. As the data is processed and object alerts aggregated, we add different statistics to different tables in our database.
The main tables in our database are the objects table which contains basic descriptors such as location, number of observations, and basic magnitude statistics; the detections and non_detections tables which contain the object light curves including their detections and non–detections; the features_v3 table which contains the object light curve statistics and other features used for machine learning classification; the xmatch table which containes the object cross–matches and associated cross–match catalogs; or the stamp_classification and late_probabilities_v3 tables which contain the object classification probabilities, including those from the early and late classifiers.